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Imara Corporation Launches Its First High-Power Lithium-Ion Battery Cell

Energy Density vs. Power Density for the 18650HP1 Click to enlarge.

Li-ion start-up Imara Corporation (earlier post) announced that its first 18650 high-power lithium nickel manganese cobalt oxide cells are now available. Imara is providing battery cells to customers in the power tool, outdoor power equipment and transportation markets.

The cells offer a volumetric energy density of 350 Wh/L, and a gravimetric density of 135 Wh/kg. Nominal capacity is 1510 mAh, and nominal cell voltage is 3.7V. The 18650HP1 offers a high lifetime energy delivery of 6.8 kWh, according to Imara.

Imara’s technology is materials-agnostic; with the lithiated nickel-manganese-cobalt (NMC) oxide cathode, the technology allows Imara to get a high rate without blending the NMC with a manganese spinel (as Sony and Sanyo do).

The process creates a cathode with very low impedance, stable cycle life and high current carrying capacity. The initial core technology, exclusively licensed from the Stanford Research Institute (SRI), was developed and funded in conjunction with the US Department of Energy as part of the Partnership for the Next Generation Vehicle (PNGV) initiative.

Imara says that it is ramping up high-volume US-based production of electrodes, leveraging its proprietary materials technology. The company says it is also developing large format cells for the automotive and grid storage markets.



Excellent for competition. More producers the better.

Henry Gibson

ZEBRA batteries, not cells, are about 120 watt hours per kilogram fully enclosed in their insulated case.

What is an estimate of the energy density of batteries made from these cells because for automotive systems like the TESLA they require protective circuits and air conditioning.

It would be nice to get a cost estimate. The life estimate avoids the common number of cycles estimate.

From now on all electric car manufacturers and battery manufacturers should be required to give the present cost per mile for their batteries with the assumption that a mile takes 200 watt-hours of electricity. This cell has only 34 miles in it and this does not consider the electrical cost to charge it. It also does not consider the cost of the motor and the power electronics and the charger.

One report gives the price of $3000 dollars for TESLA to just install a high power outlet in their purchasers garage. A person does not have to spend that much for an adequate working car. ..HG..

Neil Maguire

The Imara cell is targeted at high-power applications. The Zebra battery, in addition to the operational challenge of operating at nearly 500 degrees F has approximately 150 W/kg power. This is not a feasible solution for hybrid and short range PHEV's which Imara is targeting. These vehicles are limited today by power capabilities of batteries. With Imara you get the cycle life of an A123 iron phosphate but without the huge sacrifice of energy density.
Thanks for you interest!

Henry Gibson

Yes the commercial ZEBRA batteries have a power limitation. They also could be made in tiny cells and have better power. Where power is an issue, flywheels might be a cost effective solution, but obviously not in screw-drivers.

The user of the ZEBRA battery is shielded from the heat with the vacuum panel insulation. The high temperature and insulation is an advantage for operating in hot and cold climates. Only very simple blowers are needed to cool the cells.

There is the real disadvantage that the ZEBRA will stop working when the battery cools below operating temperatures, but the charge can remain forever until the battery is reheated. A nickel-hydride battery can preserve the hybrid function when this happens and a very high power heater can be used to reheat the battery into full function.

The major falacy about electric cars and plug-in-hybrids is that high power and high energy density batteries are needed for their useful operation. Tzero, AC propulsion, proved this to be false with their operation with and without a range extender on lead batteries. This literature was on their site until a few months ago. The EV1 was also an adequate success with lead or nickel hydride batteries.

General Electric is going to use the ZEBRA battery in its future hybrid locomotives and has tested them in several prototypes. Their hybrid mining trucks will also use them.

The Prius may as well have been built with a flywheel and would have the same economy if it were but could have better acceleration. Flydrid proposes a geared mechanical flywheel with good arguments and prototypes. They are cooperating with an electric version as well.

Parry People Movers have two commercial flywheel hybrid vehicles in revenue operation.

The zinc REVOLT threatens lithium batteries even but also fuel cells. Best wishes. ..HG..


Divide the lifetime energy (6,800 Wh) by the cell capacity (3.7 x 1.51 Wh) and you get 1,217 cycles.

I wonder how far the discharges are and if that is to 80% capacity at end of life?

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